Patients with HIV-disease continue to be treated with highly activated antiretroviral therapy (HAART). However, our research group and others have shown that vision loss and neurological loss continues to occur despite elevated CD4 counts. We have previously shown that we are able to visualize subtle retinal changes associated with healed cotton-wool spots (CWS) up to 16 years after the active phase. In this grant we plan to study the group of subjects that continue to exhibit neurological changes and retinal damage. Our hypothesis is that retinal damage is associated with neurological changes. Our first specific aim is to quantify retinal damage by high-resolution adaptive- optical corrected OCT. Our second specific aim is to develop a computer algorithm to map the defects associated with healed CWS. Our results have indicated that healed CWS demonstrate a characteristic restructuring of the retinal layers. This restructuring can be mapped in 3-D OCT images. The third specific aim is to correlate structural retinal defects with neurological markers collected by our collaborators at the UCSD's HIV Neurobehavioral Research Center. A possible correlation might help us by using retinal structural markers as indicators for neurological damage. Our team of collaborators includes experts on retinal imaging, computer processing, and neurobehavioral research.